Figure 1.
Responses to vertical translation on a manually driven spring-assisted chair. The stimulus frequency was approximately 1.5 Hz. A. Example of a response during translation in complete darkness. Head velocity was calculated from the accelerometer signal as described in the Methods. Head velocity is inverted for easier comparison to eye velocity (vertical component of angular eye velocity). B. Response sensitivities (eye velocity / head velocity). These were calculated by robust linear regression (rlm in R / rpy, www.cran.r-project.org); the regression slope is the sensitivity.